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    <title>API Overview</title>
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	<p>
	The Fabric Gateway SDK allows applications to interact with a Fabric blockchain network. 
	It provides a simple API to submit transactions to a ledger or query the contents of a ledger with minimal code.
	 The Gateway SDK implements the Fabric programming model as described in the
	 <a href="https://hyperledger-fabric.readthedocs.io/en/latest/developapps/developing_applications.html">Developing Applications</a>
	 chapter of the Fabric documentation.</p>
	 <p>The following shows a complete code sample of how to connect to a fabric network,
	 submit a transaction and query the ledger state using an instantiated smart contract (fabcar sample).
	 </p>

    <pre><code>
    public static void main(String[] args) throws IOException {
        // Load an existing wallet holding identities used to access the network.
        Path walletDirectory = Paths.get("wallet");
        Wallet wallet = Wallets.newFileSystemWallet(walletDirectory);

        // Path to a common connection profile describing the network.
        Path networkConfigFile = Paths.get("connection.json");

        // Configure the gateway connection used to access the network.
        Gateway.Builder builder = Gateway.createBuilder()
                .identity(wallet, "user1")
                .networkConfig(networkConfigFile);

        // Create a gateway connection
        try (Gateway gateway = builder.connect()) {

            // Obtain a smart contract deployed on the network.
            Network network = gateway.getNetwork("mychannel");
            Contract contract = network.getContract("fabcar");

            // Submit transactions that store state to the ledger.
            byte[] createCarResult = contract.createTransaction("createCar")
                    .submit("CAR10", "VW", "Polo", "Grey", "Mary");
            System.out.println(new String(createCarResult, StandardCharsets.UTF_8));

            // Evaluate transactions that query state from the ledger.
            byte[] queryAllCarsResult = contract.evaluateTransaction("queryAllCars");
            System.out.println(new String(queryAllCarsResult, StandardCharsets.UTF_8));

        } catch (ContractException | TimeoutException | InterruptedException e) {
            e.printStackTrace();
        }
    }
    </code></pre>
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